The hosts threw away a 10-point lead to lose 22-16 at Kingston Park in the Aviva Premiership at the weekend - the first time they have lost the fixture in seven years.
"We had a lot of possession we just didn't know how to use it. If you can't do that you will never win a game," Richards told reporters.
"You have to replicate that time and time again and unfortunately we don't seem to be able to do that time and time again. That comes back to control and energy as well.
"Some of the boys aren't quite fit enough and a couple of the boys are carrying bugs from last week as well and we just need to make sure we look at ourselves in the eye and go out and train and play as we train."
Newcastle travel to Sixways to face Worcester Warriors on Saturday.